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Continuing R 50/2 saga

johncrute

New member
Put in new plugs, and the bike started right up. But now, can't seem to get carbs adjusted well enough to make it run very good. Carbs were cleaned, and all new gaskets and floats installed. Will start, but not accept throttle. Tried adjusting per Clymer manual, but when I pull a plug wire to adjust the idle screw, it will die. Kept trying for a couple of hours,but to no avail. Also replaced plug wires, as originals were shot. Cleaned shut off valve, and found some junk, but inline filters are clean. Sometimes now when starting, it will rev for a while before idling down. Just doesn't seem to be any consistency here. Any suggestions?
 
Uneven Running

Sounds to me like an air leak between one or both carbs and head. Slight leak would also account for sometimes revving up, until expansion from running reduced size of the leak. You might get it started, then move an unlit but on propane torch around the area. If it's a leak, the propane will enrichen the mixture. Good luck, can be a pain to track.
 
These are so simple

Not knowing what you have done so far(no history in thread)I would strongly suggest start wit basics. Make sure both your coil to plug wires are very snug at coil and plug and make sure you have good spark at the plug sometimes you will have some spark but it just isn't enough. Check and make double sure your points are good and timing is good.

Carburetors can be dirty mainly the idle jet and you would get a crappy idle and it will not take throttle just as you described. Pull your idle jet, air adjust screw and throttle slide and make sure the air fuel passage for idle circuit is clean. Now take that little jet and make sure it is clean. I use a single stand of stainless brake cable to get the opening in the jet clean and a bundle of 3-4 to clean around the edge of top and bottom of the jet. The book and common sense tell you not to do this because the jet is soft metal and can be damaged or you can brake the wire off inside so just be gentle and careful. You also want to make sure your throttle cables are set correctly and move freely.

It sounds to me like its one or both of the idle jets as I have 3-4 /2s in the stable and that's what happens when they have sat for more than a couple weeks.

Like I said they "they are so simple" its easy to get carried away and make the trouble shooting all lot more involved and harder than it should be.
 
Update on R 50/2

As it turns out, there were a number of things that needed attention. The main thing was that the mounting flanges on the carbs were warped. Put some sticky 80 grit sandpaper on a concrete floor, and sanded them flat. Only took a few minutes each to do. Idles fine now.
 
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